XFI tip? Stalls when shifting from Park to D or R

[GN SBS]

Hi folks,

I'm running XFI and am looking for a quick tip. My current tune stalls when I shift from Park to drive or reverse.

I can ride the brake and give her gas to prevent it, but would rather not have to. Doesn't seem to be sensitive to whether the car has just been started or running a while. Happens whether I'm running my pump gas or E85 tune.

Any ideas would be much appreciated. I can email a log file with a stall in it if that would help.

Thanks!
Scott

 

[Onalky87]

I'm prolly wrong but, mine does the same sometimes. I was told it was Bc of the vig converter in it

 

[norbs]

It is probably going lean during the shift. Raise up the ve numbers around idle slightly, and make sure you dont have huge number difference between adjacent cells. You will want to tune the cell in gear hot idle to have minimum correction, a few -%. Try setting your a/f to as lean as you can go without surging. Then you will know what the motor likes for a/f at idle and richen slightly to avoid the surging. The car needs to be warm and a good drive 30 min drive to get everything hot. Once this is adjusted and you still have issues you need to work afterstart enrichment and cold start enrichment. Remember cold start is the first 5-8 min run time and after start is about the first 1-2 min or run time. You need to have a mix or both in your program. All these items can be logged in the fast, CTS coolant temp corr., AFT. corr are the terms.

 

[HighPSI]

It is probably going lean during the shift. Raise up the ve numbers around idle slightly, and make sure you dont have huge number difference between adjacent cells. You will want to tune the cell in gear hot idle to have minimum correction, a few -%. Try setting your a/f to as lean as you can go without surging. Then you will know what the motor likes for a/f at idle and richen slightly to avoid the surging. The car needs to be warm and a good drive 30 min drive to get everything hot. Once this is adjusted and you still have issues you need to work afterstart enrichment and cold start enrichment. Remember cold start is the first 5-8 min run time and after start is about the first 1-2 min or run time. You need to have a mix or both in your program. All these items can be logged in the fast, CTS coolant temp corr., AFT. corr are the terms.

Or you could just rescale the VE table correctly...

 

[GN SBS]

Thanks for the feedback.

I'm looking at the log for one stall and actual A/F ratio does not change much (9.00 to 8.88) as the stall begins. 02 correction < 4%.

The only parameter I was logging that shows a marked increase or decline was the IAC target. I wasn't logging CTS coolant temp corr. or AFT. corr & will try again tomorrow and see.

Other ideas welcome. Thanks folks.

 

[HighPSI]

What does the MAP do?

 

[Craig Smith]

This can be a tricky area to tune on some cars. Most important thing IMO is to make sure the IAC motor is only slightly open at a hot idle in park, like 15 counts or so at the most. Try taking some timing out of it around the idle region too.

 

[GN SBS]

What does the MAP do?

MAP (psia) drops from -7.9 to -9.3 in the first 0.3 sec after shifting and then starts climbing again to -5.6 just before it stalls half a sec later.

 

[TurboDave]

It seems that everybody that is plagued with this issue all have the same thing in common.....

If you're running a 7 disc vigilante, you've discovered your problem.

Mine's been doing it ever since I had mine installed years ago, and haven't found a way around it. Except to get the converter redone to less clutches, but that's never been in the budget, I just live with and have learned how to feather the throttle when shifting out of park.

I've played with my VE table till I was blue in the face, but couldn't cure it.

the 7 disc vig. are indestructable at our level, but have this one flaw in common.

 

[GN SBS]

It seems that everybody that is plagued with this issue all have the same thing in common.....

If you're running a 7 disc vigilante, you've discovered your problem.

Interesting. I switched to a 4L80e and am indeed now running a multi-disc vigilante instead of the single disc I used to run with the 200.

Perhaps -that- is the variable that changed as the tune worked well before.

Thanks again to all who've taken the time to offer feedback.
Other thoughts welcome!

 

[norbs]

You need to make the car richer and it wont stall. If its doing it cold its your adjustments as I described earlier.